function array_values (input) {
  // http://kevin.vanzonneveld.net
  // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
  // +      improved by: Brett Zamir (http://brett-zamir.me)
  // *     example 1: array_values( {firstname: 'Kevin', surname: 'van Zonneveld'} );
  // *     returns 1: {0: 'Kevin', 1: 'van Zonneveld'}
  var tmp_arr = [],
    key = '';

  if (input && typeof input === 'object' && input.change_key_case) { // Duck-type check for our own array()-created PHPJS_Array
    return input.values();
  }

  for (key in input) {
    tmp_arr[tmp_arr.length] = input[key];
  }

  return tmp_arr;
}

array_values( {firstname: 'Kevin', surname: 'van Zonneveld'} );

{0: 'Kevin', 1: 'van Zonneveld'}